The present invention relates to a textile laminate and a method of fabricating the same, and more particularly, to a waterproof and breathable textile laminate and fabrication method thereof.
A wide variety of air and water vapor permeable materials have been developed for different purposes. For example, these materials can be used in filtration, separation, and apparel. U.S. Pat. No. 5,928,582, for example, discloses a method of forming a microporous membrane that utilizes an ultraviolet irradiation process to form microsphereulites, followed by a thermally-induced phase separation, yielding microporous membranes that have improved flow and mechanical properties. In U.S. Pat. No. 4,194,041, Gore et al. disclose a waterproof laminate for use in constructing sport apparel having air and water vapor permeability with liquid water resist properties.
Breathable waterproof laminates are particularly advantageous in traditional waterproof textile fabric applications, such as garments. A garment formed of conventional waterproof textile fabric can prevent environmental water, such as rain, from entering the garment, but often tends to be uncomfortable to the wearer, as moisture, such as perspiration, cannot evaporate through the garment. The moisture generally remains trapped in the garment.
Continuous development of the waterproof material has greatly improved breathability of the waterproof garments. Breathable waterproof material is a microporous film comprising a plurality of pores with a size about 1/20000 of liquid water droplets and 700 times that of water vapor. Thus, breathable waterproof material can prevent water from penetration while allowing air and water vapor to escape.
Typically, the waterproof textile laminate for a garment includes a plurality of layers for various functions, such as a fabric layer with thermal regulative property. Accordingly, adhesive agents are required during the manufacturing process to combine these multiple layers. In order to avoid delamination, the adhesive agent must be coated over a majority of each layer. Most adhesive agents, however, are hydrophobic and have very low water permeability, leading to significant deterioration of the water vapor permeability of the textile laminate as the water vapor cannot pass through the adhesive agents. In other words, the breathable ability of a garment is still limited. For example, when massive perspiration is generated due to heavy sport or a high temperature, the perspiration remains on a wearer's body until the perspiration evaporated through the breathable textile laminate gradually. This evaporation process typically takes long time and makes the wearer feels wet and uncomfortable.
In U.S. Pat. No. 5,660,918, Dutta et al. disclose a grid pattern of an adhesive layer for bonding a fabric layer and a hydrophilic layer. The improvement of water permeability, however, is very limited. Thus, a new waterproof textile laminate with high water vapor permeability is desirable.